FDA vs Food and Drug Administration

FDA and Food and Drug Administration both are nouns.

Word	Noun	Adjective	Verb	Adverb
FDA	Yes	No	No	No
Food and Drug Administration	Yes	No	No	No

As nouns, FDA and Food and Drug Administration are synonyms defined as:

FDA and Food and Drug Administration: a federal agency in the Department of Health and Human Services established to regulate the release of new foods and health-related products

FDA (noun)	Food and Drug Administration (noun)
a federal agency in the Department of Health and Human Services established to regulate the release of new foods and health-related products	a federal agency in the Department of Health and Human Services established to regulate the release of new foods and health-related products